MATERIALS - Lilium longiflorum cv. 'Croft' and 'Ace'. Tapetal development appears to parallel meiotic development as follows: Tapetal chromosomes contract markedly just prior to meiosis, as do chromosomes in late premeiotic mitosis. Tapetal chromosomes contract again during the contraction stages of meiosis, i.e., late pachytene through diplotene. Meiotic and tapetal cells are connected during these stages. This behavior thus resembles "premature chromosome condensation" in multinucleate HeLa cells and in other cells, and it may be responsible for the gradient of expression of preleptotene chromosome contraction within the anther, i.e., within the reproductive organ. Studies will include: The relation of chromosome contraction in tapetal cells and cells in premeiotic mitosis. The relation of chromosome contraction in tapetal cells and meiocytes in pachytene through diplotene stages.